Liberty High School near Issaquah has been the target of six burglaries since the start of the school year.

Investigators said the burglars are after projectors worth nearly $1,000 each.

The thefts started in August. The burglars struck twice in September and again in October, November and December.

So far, at least seven projectors have been stolen as well as computers, cameras and a scanner for a total loss of $9,422.

King County sheriff’s spokesman John Urquhart said it was unusual to have so many burglaries at one high school.

“There doesn’t appear to be any forced entry, so we’re pretty much at a loss to figure out who is doing it and how they’re doing it,” said Urquhart.

According to the school district, all of the locks were changed at the school a few of months ago and new keys were distributed to employees, but the burglaries continued.

Students said some of the teachers are locking up the projectors.